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The conventional solid-state friction welding process involves imparting a movement to one of them, bringing them closer together so that there is friction from the clamping force. By overcoming the frictional resistance on the surface of the workpieces, work converted into heat is generated. The obtained heat heats the elements to a temperature close to the melting point but not exceeding it. After stopping the movement in relation to each other, the process of pressing the elements with the force P with a greater force causes plasticization of the material and the formation of a flash. In low pressure friction welding, most of the heat required for the joining process comes from the induction coil. This means that two key process parameters such as friction time and contact force are significantly reduce. This affects the course of the process and the end result of the process of joining materials. The shape and size of the flash as well as the size of the heat-affected zone in the weld will change. Among the many advantages of this method of joining metals, one should mention the possibility of welding smaller parts, thin-walled, with complicated geometry, which the friction butt welding process would not be able to cope with. Additionally, there is a possibility of heat treatment. In order to verify the feasibility of the friction welding process with low pressure in industrial conditions, a number of tests presented in this study were carried out, together with the analysis of the results. A number of proposals for the optimization of low-force friction welding with the use of artificial intelligence have also been developed has also been developed. A simpler but less effective solution is application of neural networks. It is possible due to multiple digital recording and process automation parameters with digital recording and process automation This solution approach is not as productive as the proposed hybrid algorithm combining neural networks, fuzzy logic and genetic algorithmsThe hybrid method enables you to take advantages of all three algorithms in the position optimization.

This study is focused on research in the field of grinding cermet materials. Different grinding conditions in terms of several cutting speeds were used for grinding two cermets with different chemical compositions. A diamond grinding wheel and the same grinding strategy was used for each test. The influence of the cutting speed on the spindle load and the calculated cutting force was observed. It was found that higher cutting speed causes lower calculated cutting force but higher spindle load because of the higher RPM of the grinding wheel. This affects the grinding process and the resulting quality of the ground surface. Cracks and breakout occurred on the surface when the higher grinding wheel speed was used. The grinding wheel was dressed before each test to ensure the same grinding ability. The profile of the grinding wheel was scanned during grinding using an optical device to see the effect of the cutting speed and dressing on the wheel wear. The results of this work will be used for a better understanding of the process of grinding cermet.

In this paper, the results of an investigation done with face milling are presented. The changes in cutting force and surface roughness were studied through changing the values of depth of cut and the feed per tooth. Meanwhile the permanent value of the undeformed chip cross section, which was determined (fz and ap), remained permanent. Increasing fz and keeping the same value of Ac chip cross section, the ratio ap/fz changed in five grades from 0.5 to 8. It is shown, that if the feed is increased in the examined range so that the chip cross section is constant, then the value of the cutting force decreases, which decrease can be observed in all three force components. Accordingly, the mechanical power required for cutting is reduced. The results of the surface roughness investigations showed that initially a significant increase can be observed in the roughness with the gradual increase of the feed (up to ap/fz = 2.5), followed by a moderate increase afterwards.

The Article deals with the controlled influence of the adhesive force in contact of the road vehicle’s wheel with the road. The first section shows how the adhesive force is reduced. The next step is the familiarization with the experimental vehicle with the Alternative SkidCar, where experimental measurements were carried out, assessment of the advantages and disadvantages of the experimental vehicle with the Alternative SkidCar and the drive on the sliding surface following the experimental test methods. The objective of the article is to determine how great the difference in vehicle behav-iour is when the adhesive force changes by modifying the radial reaction and the change in the coeffi-cient of adhesion.

The atomic force microscopy is method used to obtain surface properties of various materials, includ-ing surface morphology, local magnetization, conductivity and mechanical properties. In this work the atomic force microscope was used to investigate properties of rubber compounds. Three samples made of different rubber compounds that varied in filler content were studied in order to determinate their homogeneity and ratios of their Young’s moduli. Images of their surface topography were ob-tained and then on each sample five places were chosen where spectroscopic curves representing force – distance dependence were scanned. Parts of these curves from which Young’s modulus can be determined were approximated by linear functions and their slope was calculated. Slope values close to each other suggest similar values of Young’s modulus. By their comparison it was determined whether even distribution of ingredients in rubber compound can be assumed and thus the blending process to produce these compounds can be considered sufficient.

Increasing the efficiency of cutting operations while fulfilling the required (expected) quality of the parts constantly requires a thorough knowledge of the chip removal process. This is especially justi-fied in the case of deviations from the usual (traditional) technological conditions or cutting data, both in terms of cutting theory and technique. This paper summarizes some of the results of a study of cutting force and cutting temperature in face milling. The technological analysis of face milling was performed by FEM simulation, which was compared and validated by measuring the cutting force. The chip removal of C45 rolled steel as a function of tool rotation was studied with two differ-ent depths of cut ap and feed rate fz so that at a constant nominal Ac cross section the ratios ap/fz were 0.1 and 10. The effect of the change of the cross-section and chip ratio is shown.

Modelling of cutting forces is important for understanding and simulation of the machining processes. This paper presents cutting force modelling of data obtained from machining of C45 carbon steel with a coated carbide tool. The model is based on a rather extensive measurement of 270 combinations of cutting tool geometry parameters (rake angle, clearance angle and helix angle), tool wear (flank wear average value), chip thickness and cutting velocity. The model with the friction and cutting component of the cutting force is presented and discussed. We conducted an analysis of the identified model and found a relationship between the increase in tangential and radial cutting forces and tool wear. We concluded that flank wear influences the cutting force acting on the worn tool more significantly than cutting tool geometry. This is caused by changes in cutting edge geometry and the resultant significant increase in the friction component of the cutting force as is shown using the identified model.

Currently, there is a demand in the aerospace industry for a more effective and non-invasive milling technique for powder metallurgy γ-TiAl alloy. The primary objective of this research is to examine the surface milling process of a γ-TiAl alloy generated by powder metallurgy. The primary objective of this study is to examine the impact of process parameters on the surface roughness and cutting force of the alloy, with the aim of optimizing both surface roughness and cutting force. The response surface method was implemented to examine the milling process, and the NSGA II algorithm was employed to optimise surface roughness, cutting force, and material removal rate. The findings indicate that the cutting depth exerts a significant impact on both the surface morphology and surface roughness. The available data indicates a clear correlation between the depth of cutting and the rate of feed, as well as the resulting assessment of surface roughness. Nevertheless, the first rise in spindle speed is associated with a subsequent increase in surface roughness, followed by a subsequent drop of a lesser magnitude. A minimal threshold for surface roughness has been established at 0.203μm. The spindle speed exerts the primary impact on the cutting force. There exists a positive link between the cutting force value and both the cutting depth and feed speed, as the cutting force value has a positive correlation with the incremental changes in these variables. Nevertheless, the relationship between cutting force and the observed trend is non-linear, exhibiting an initial decrease followed by a rise when cutting force is augmented. The minimal cutting force necessary was quantified as 112.3 N. Subsequently, a regression analysis was employed to develop a correlation model between surface roughness and cutting force. and machining parameters. The confirmation of the coefficients' validity in the model was achieved via the utilisation of analysis of variance (ANOVA) and residual analysis. The main goal of developing a machining parameter optimisation model is to limit surface roughness and cutting force, thereby improving operational efficiency. The NSGA-II method is utilised to tackle the problem of multi-objective optimisation, leading to the attainment of the optimal parameter solution. The purpose of the verification test is to evaluate the precision of the forecasts generated by the optimised model. The work holds importance in its analysis and juxtaposition of diverse processing factors, alongside the use of multi-objective optimization methodologies.

Scratching force is a significant factor to evaluate the characteristics of single diamond grit scratching process. In this paper, experimental study was carried out to investigate the vibration characteristics of force signals during the scratching process. A precise multicomponent dynamometer is employed in the force measurement during a single diamond grit scratching on pure copper. The frequencies of the vibration section of force signals with different scratching parameters are calculated and analyzed. The influence of force signal vibration on the measuring accuracy of dynamometer is systematically analyzed further. The results show that higher scratching speed and larger scratching depth lead to larger vibration amplitudes of the force signals. Strong impact on the quartz piezoelectric crystal of dynamometer, which is produced indirectly by single diamond grit scratching process, leads to the vibration of scratching force signal. The first semi-sinusoidal force signal is the actual scratching force. The vibration of the scratching force signal has little effect on the measuring accuracy of the dynamometer.

Workpiece fabrication of titanium alloy is widely used in several high-end fields. In this study, finite element analysis of titanium alloy turning process is carried out and the turning process is modeled by using material properties and intrinsic equations. Then the power transmission of centerless lathe is controlled in the machining process, so as to obtain the performance calculation of different process parameters on cutting force, chips, and residual stress. The analysis of the simulation and experimental data yielded that when the tool travel speed was 1 m/min, the radial force increased to a maximum value of 150N. When the depth of cut was 0.3mm, the radial force was 151N and then increased to 200N. In the comparison of the simulation results, it was concluded that the depth of cut was 0.3mm, the minimum error value was 7.43%. In the quality analysis, the optimum parameters for travel speed and depth of cut were 1.0 m/min and 0.2mm respectively. When the spindle speed was 480 r/min, the roughness of the machined surface of titanium alloy was closer to the simulation results, and the lowest difference was 0.1 μm. Therefore, the finite element machining model of titanium alloy turning proposed by the study could effectively improve the machining quality and accuracy, and it has superiority. In the future machining and parts manufacturing, it can improve the processing efficiency and promote the optimization of titanium alloy material properties.

Grinding of cermet was studied to determine the impact of the depth of the cut on the grinding process and the final quality of the finished surface. Depth of cut is an important cutting parameter which affects the whole grinding process in terms of grinding stability, cutting forces, vibrations, spindle load, etc. It is also connected with other cutting parameters such as cutting speed and feed rate which should be optimized to ensure the required surface quality in the required process time. The effect of different depths of cuts on the surface quality in terms of roughness was observed during grinding of two types of cermet rods. An IFM G4 optical device was used for monitoring the surface roughness during tests. The progress of the spindle load was monitored on the grinding machine during grinding. This was used for calculating the resulting cutting forces. Experimental grinding was carried out with a diamond grinding wheel which was dressed before each grinding test. The results of this work will be used for better understanding of the process of grinding cermet.

Ultrasonic vibration cutting technology for processing difficult-to-cut materials proposed a new machining method to improve the cutting performance, is an effective measure to improve the surface quality and cutting efficiency, widely used in titanium alloys and other difficult-to-cut materials. This paper is based on the development of related technology research at home and abroad, first from one-dimensional ultrasonic vibration cutting, two-dimensional ultrasonic vibration cutting, three-dimensional ultrasonic vibration cutting three dimensions to high-speed ultrasonic vibration cutting to carry out the analysis, and then from each dimension of turning, drilling, grinding and milling and other different ways of cutting mechanism, cutting force, surface quality, device development, tool design and other directions of the systematic analysis and research. The analysis results show that ultrasonic vibration cutting technology provides new technical solutions and methods to solve the problems of low efficiency and low dimensional accuracy in processing difficult-to-cut materials by ordinary cutting technology, and can provide technical support for the processing of difficult-to-cut materials. Finally, it looks forward to the future trend of ultrasonic vibration cutting technology: in the future, the integration with five-axis machining technology, additive manufacturing technology, microscopic inspection technology, 5G communication technology and other cutting-edge technologies will be the development direction of ultrasonic vibration cutting technology.

Springback of v-type sheet metal must be controlled during the high precision forming process. While, variable blank-holder force technology is an effective measure to control sheet metal springback, but it only overall control the stampings. The project was put forward through the v-type sheet's variable blank-holder force and adjustable drawbead to control springback, which is place electric adjustable step drawbead around the blank-holder. Changing the blank-holder force, meanwhile, adjusting the height of the drawbead according to the needs of the stamping real time, so as to control the quality of sheet forming. To get the optimal combination of variable blank-holder force and adjustable drawbead, this rearch for the technology to control the springback, which has carried on the theoretical analysis and numerical simulation, then providing test for it.

Investigation of cutting forces in metal cutting is of great importance for defining the effectiveness of the production as well as its impact on product quality. Several researchers studied the effect of cutting parameters on the cutting forces through statistical analysis; however, very few studies use the normalization of the data. Normalization reduces the skewness in the data and increases the accuracy of the results, which can be beneficial in modern industry where AI is being integrated with manufacturing. This research aimed to study the statistical analysis of cutting parameters and cutting forces using log-normalization and compare the accuracy of results with absolute data. The study uses a three-axis piezoelectric dynamometer to measure the cutting forces in the turning of X5CrNi18-10 steel. The results suggested that feed influences the cutting forces during machining. Coolant helps to reduce the cutting forces during the turning of hard steel. Log-normalization increases the accuracy of the results. These results can be used to predict cutting forces during the turning of chromium-nickel alloy steel.

Corrosive damages can lead to accidents on pipelines in various industries. Therefore, the main objective of the work is to study the peculiarities of the development of internal corrosion at the corners of turns in steel pipes. The paper discusses the development of corrosion. It substantiates the primary importance of the development of corrosion on curved sections of steel pipes. It has been established that, in curvilinear areas, the rate of corrosion development depends on the rate of fluid flow, on the number of ions, and also on the effect of centrifugal force. The authors studied the average rate of corrosion development at the turns of hydraulic structures. Thus, the results obtained showed that the location of steel pipes of hydraulic structures affect the rate of corrosion development from inside the pipes.

This article deals with benefits of PVD and CVD coatings applied to cutting inserts during face milling technology. The coatings deposited on applied cutting inserts were used to extension the tool life. Machining process was carried out on the conventional vertical milling machine tool. This machining process was performed without coolant. The set up of cutting conditions were constant throughout the machining and low-alloy Cr-Mo steel DIN 42CrMoS4 (W. Nr. 1.7227) was used as workpiece material in the realized process of experiments. The aim of this investigation was to compare coated and uncoated changeable cutting inserts clamped in the milling cutter and find out the benefits of PVD or CVD coatings during realization of face milling process. The monitored parameters were the force load measured by piezoeletrical dynamometer Kistler 9257B and the obtained flank wear measured by optical microscope.

Joining technologies are very important aspects of production process in the automotive. Especially regarding the use of newly developed types of materials (e.g. ultra high-strength steels or aluminium alloys), in addition to welding technology, e.g. riveting or adhesive bonding technologies are used. Submitted article evaluates the effect of the riveting force on the final quality of riveted joint when joining aluminium alloy EN AW-6016 (thickness 2 mm). The actual evaluation of the riveted joint was carried out using a shear test, measuring the hardness HV01 and deformation analysis of specimen using non-contact optical scanning (ATOS III Triple Scan system).

This study examines the two-pass hot rolling process of 6061 aluminum alloy wire, focusing on forming load measurement to evaluate process stability and its effects on dimensional accuracy and mechanical property uniformity. Using response surface methodology (RSM), process parameters and forming loads were analyzed to assess their influence on mechanical property distribution and verify the applicability of load measurement in process quality evaluation. A full-factorial finite element simulation was conducted to investigate the effects of pre-forming section reduction rate, material temperature, roll speed, and friction coefficient. Experimental results indicate that forming load measurements effectively capture variations in initial wire temperature and reveal the influence of material velocity and roll speed. Load data also identify the Spike phenomenon caused by improper roll positioning, leading to abnormal load surges and reduced mechanical property uniformity. The strong agreement between experimental forming loads and FEM simulations validates the reliability of the proposed measurement method. This study provides a basis for wire rolling process design and machine learning-based quality prediction, supporting advancements in smart manufacturing applications.

Face milling is one of the most common machining processes used for the production of high quality flat surfaces. Another important feature of the process is the high material removal rate that can be achieved, or in the case of milling performed at one pass, the high surface rate. Surface rate is increased by increasing feed and cutting speed; both are bound by technological limitations and are limited to rather small variations, especially cutting speed. In finishing face milling, if feed per tooth is increased, subsequently the shape of the chip cross section is altered. This results in the change of the loads of the cutting edges, which influences the cutting forces and process efficiency. In this study, an experimental investigation is carried out in order to determine the influence of feed on chip size ratio. For this purpose, five different values of feed, at two different cutting speeds are tested for face milling. It is concluded that an increase in feed from 0.1 to 1.6 mm results in eight-fold increase of cutting force Fc while surface rate proportionally increases 16 times and specific cutting force only 0.5 times.

Design and technological development of cutting tools represents a fluent process that combines new knowledge from all usable technical branches with actual needs and development results of component base, production technology and machine tools. The main factors which nowadays accelerate the development of cutting tools are constantly increasing demands to improve efficiency and productivity while reducing operation costs, the application of hard machinable materials, environmental protection issues, health and growing demands for greater safety. The article deals with methodology of measurement and evaluation of cutting forces and cutting torque at a special reaming head MT3 from FINAL Tools Inc. Solution of force loading during reaming by these modern tools enable to analyse the causes of cutting tool deficiencies starting from coating suitability up to weaknesses in their design. The article also analyses the significance of the reaming process from the reaming view point using a process liquid, including a tool life analysis combined with the tool wear.

The determination of the ploughing forces is necessary for wear monitoring of the cutting tool in micro cutting. The extrapolation method on zero cut chip thickness is used very often to determine the ploughing forces. But there are many opponents of the extrapolation method on zero uncut thickness. The aim of this research was to increase the accuracy of determination of the ploughing force and to investigate the effect of processing materials and cutting tool wear on the ploughing force values. To achieve this aim was used the method comparing total forces at different flank levels of wear to determine the ploughing forces. The experiments were performed by cutting of aluminum alloys, structural steels and stainless steel with different cutting tool wear.

In this paper, the electric discharge perforation technology is used to preset surface texture, which effectively suppresses the generation of large cutting forces in the hard cutting process, avoids the aggravation of tool wear, and improves the service life of the tool. Use CBN tools to hard-cut GCr15 hardened steel, design three-factor non-textured orthogonal cutting simulation and experiment about cutting depth, cutting speed, and feed rate, and use range, variance and signal-to-noise ratio methods to simulate and experiment data is analyzed to determine the best combination of cutting parameters and the degree of influence of each parameter on the cutting force generated in the hard cutting process. Use the best combination of cutting parameters to hard-cut GCr15 hardened steel with a preset surface texture, observe the tool wear, measure the cutting force, compare and analyze the results under the same cutting conditions without texture to verify the preset surface texture can effectively reduce tool wear and increase tool life.

The article describes a pilot experiment of mechanical testing of 3D printed vertebrae with an inserted screw. The main goal of this work was to verify the design of a measurement methodology for experimentally determining the mechanical properties of vertebrae produced using 3D printing and also for determining the load-bearing capacity of a screw when it is drilled into a vertebra. The work describes the construction of a special fixture with which it is possible to clamp test samples for tensile testing. The stud screws were pulled out of a real or printed vertebra using a tearing machine. Testing was performed on porcine and 3D printed vertebrae. CT images of porcine spines obtained by a computed tomography scanner were used to create the printed vertebrae. This work verified the mechanical properties of printed and real vertebrae. In connection with this work, suitable printed materials and the necessary parameters of 3D printed samples will be sought so that they correspond to the necessary mechanical properties and can replace human vertebrae. It will then be possible to conduct laboratory investigations to obtain better results in spinal stabilization. The experiments verified the measurement methodology, compared the measured values between real and printed vertebrae, and also determined the next direction of research.

The Edge Localized Mode coil is the key component to prohibit the phenomena of disruptive instability occur-ring in the edge of Tokamak plasma. And the coil is made of Stainless Steel Jacketed Mineral Insulated Con-ductors. The different pieces of conductor are connected by joints. During the normal operation of Tokamak device, the joint will be shocked by electromagnetic and thermal loads. Thus, it is necessary to perform the mechanical analysis to verify whether or not the ELM joint has sufficient safety margin to resist the impact of coupling field. In order to obtain the load boundary condition for mechanical analysis, the electromagnetic and thermal analysis are launched first. Then the temperature and electromagnetic force density are inserted into the mechanical analysis model. And the equivalent stress is calculated. The analysis results indicate there is stress intensity at the component of supporting rail. To mitigate the stress intensity, the local structural optimi-zation design is employed. Finally, the stress evaluation is carried out based on analytical design. The assess-ment results demonstrate the optimized model has sufficient safety margin to withstand the combined action of multiple loads.

This study presents the Resistance Spot Welding (RSW) process of Deep Drawing Steel (DDS) optimization using Response Surface Methodology (RSM) and Simulated Annealing (SA). The RSW process was optimized to obtain the maximum shear force the DDS can withstand. The experiment was conducted under various DDS thickness, welding time and welding current. The experimental processes were conducted using L16 orthogonal array, which has nine rows. The processed DDS was tested using tensile testing machine which will generate the amount of shear force that it can withstand. RSM is first used to develop a suitable mathematical model. The model was tested using Analysis of Variance. From the test result, the model then was used as the objective function of SA. Based on the result, the maximum shear force can be well predicted, which leads to reduced cost and improved welding quality.

In micro cutting it is necessary to control the cutting tool. Monitoring of cutting tools is usually accomplished by measuring cutting forces. In order to improve the accuracy of monitoring it is required to consider the ploughing forces. The ploughing forces substantially depend on the processing materials. This article describes the investigation of the effect of processing materials on the ploughing force values. The extrapolation method on zero cut chip thickness was used to determine the ploughing forces. The experiments were performed by cutting of aluminum alloys, structural steels, bronzes and stainless steels.

A four factors and three levels orthogonal milling force (MF) test is designed, which qualitatively obtains the influence of four factors, namely workpiece material, workpiece diameter, milling speed and feed per tooth, on MF of the new cold saw blade milling cutter (NCSBMC), then further verifies the reliability of test data with simulation analysis of MF. The multiple linear regression analysis and deep neural network (DNN) are used to accurately fit and predict the magnitude of MF in three directions of NCSBMC, taking into account the influence of workpiece material factors on MF. Compared with the results of empirical formula, DNN has higher prediction accuracy. The research results provide theoretical guidance for the optimization of milling parameters in actual machining process.

Results of an experimental research of friction coefficient in "alumina ceramics - quartz glass" friction pair are presented. The research with pin on disc test configuration using SRV-III test machine was carried out at loads from 10 to 1000 N, constant sliding velocities 5 mm/s; ambient temperature 23°C and relative humidity 30%. The obtained results reveal that in general, friction coefficient for "alumina ceramics - quartz glass" pair decreases with the increase in normal load. It is shown that the obtained friction coefficients values at the normal force from 100 to 1000 N for the given experimental conditions can be used to pre-estimate the interference fits in "alumina ceramics - quartz glass" friction pairs.

The vertical stability coil is a set of active feedback control coil that is used to deal with the vertical instability of plasma. To improve the response performance, the coil is mounted in the vacuum vessel, which denotes the coil-body will suffer from large electromagnetic force from the plasma current and poloidal field coils. Besides the current flowing in the feeder is nearly perpendicular with magnetic field originated from toroidal coil. It implies large electromagnetic force will be generated on the feeder. In order to withstand the impact from the electromagnetic force, a series of reinforce compo-nents are designed and installed on the coil. It is necessary to verify whether or not the coil conductor and auxiliary components could successfully bear the shock of large electromagnetic force. A three-dimensional magnetic field model is built to accurately calculate the magnetic field and electromag-netic force. Corresponding to the magnetic field calculation model, a more detailed me-chanical anal-ysis model is created to launch the electromagnetic-structural coupling analysis. Based on the stress analysis results, the local structure of the coil is optimized to decrease the peak stress. The updated model is reanalyzed and stress linearization is exerted to extract the different kinds of stress on the coil components. Finally, the stress is evaluated based on ASME analytical design. The evaluation result is helpful to guide the further design optimization.

This research pertains to rock cutting used negative rake angle. The parameters used are negative rake angles of 0o, -5o, -10o, -15o, -25o, -30o, and -40o. Negative rake angle is known to play an important role in rock machining. Negative rake angle produces more chips powder in front of the tool surface. The interaction between these particles affects the thrust force that suppresses the rock surface. A large thrust force generates hydrostatic pressure around the tooltip. According to the findings of this research, negative rake angle -25o leads to the largest thrust force and smallest surface roughness for 15.17 N and 1.21 ?m, respectively with smooth and uniform chips. The rock surface and the resulting chips powder was observed by scanning electron microscope (SEM) in order to prove the effect of hydrostatic pressure working on the tooltip. Meanwhile the hydrostatic pressure changed the brittle cutting mode into a brittle-ductile cutting mode.